It’s tucked away in the web interface, but Linux users are able to vote for features and show that they exist as part of the userbase.
I just started using Proton, but I don’t think any of their apps are available for Linux natively, which is disappointing. I mostly use Proton apps inside Ferdium which I find useful for combining all of my productivity apps and Ferdium basically just keeps a website loaded, and websites are always cross platform compatible. I would love to know if there’s a timeline for Linux apps in mind.
Proton is making an official native Linux client.
Source :
"Frequently Asked Questions :
Is the Proton Mail desktop app available for Linux?
The Proton Mail desktop app is currently available for macOS and Windows. We’re working on a Linux version that will be available in early 2024. Until then, if you use Linux, we recommend using the Proton Mail web app(new window) or Proton Mail Bridge for Linux."